Effect of n-3 fatty acids on immune function in broiler chickens

Significance of successive feeding of sources of n-3 fatty acids to broiler breeders and their progeny on growth performance, intestinal lesion scores, lymphoid organs weight and plasma immunoglobulin A in broiler chickens challenged with Eimeria

The study examined the effects of successive feeding of sources of n-3 PUFA to broiler breeders (BB) and their progeny in broiler chickens challenged with Eimeria. The BB were fed: 1) control (CON), corn-soybean meal diet, 2) CON + 1 % microalgae (DMA), as a source of DHA and 3) CON + 2.50% co-extruded full fat flaxseed (FFF), as a source of ALA. Eggs were hatched at 34, 44, and 54 wk of age. Posthatch treatments (BB-progeny) were: CON-CON, DMA-CON, FFF-CON, DMA-DMA and FFF-FFF with diets formulated for starter (d 1-10) and grower/finisher (d 11-42) phases. All chicks were orally challenged with Eimeria (E. acervulina and E. maxima) on d 10. Relative to CON, DMA and FFF increased concentration of n-3 PUFA by ≥ 2-fold in hatching eggs and progeny diets. There were no (P > 0.05) interactions between treatment and BB age on d 0 to 10 growth. In general, BB age affected (P < 0.05) growth performance throughout the study. In the starter phase, successive exposure to DHA and ALA improved FCR over CON-CON (P < 0.01). The interaction between treatment and BB age in grower/finisher was such that DHA exposure to younger BB resulted in poor growth performance (P < 0.05) relative to exposure to older BB. In contrast, exposure to ALA had similar (P > 0.05) growth performance irrespective of BB age. Moreover, successive exposure to ALA resulted in higher BWG, breast weight and lower FCR compared to successive exposure to DHA (P < 0.05). There were no (P > 0.05) interactions between treatment and BB age on the intestinal lesion scores, lymphoid organ weights and concentration of plasma immunoglobulin A (IgA). Successive exposure to DHA resulted in higher (P = 0.006) jejunal lesion scores than CON-CON birds. The results showed that successive exposure of DHA and ALA improved FCR relative to non-exposed birds in the starter phase. However, responses in the grower/finisher phase depended on n-3 PUFA type, with birds on successive ALA exposure supporting better growth and breast yield than birds on successive DHA exposure.

Investigating the impact of linseed supplementation, rich in omega-3 fatty acids, on the expression of immune genes in Beetal Goats

The present study investigated the effect of linseed supplementation on serum profiling and differential expression levels of IL-2 and TLR 2 genes involved in the immune system of lactating goats. The study was conducted on 15 lactating Beetal goats for 3 months, which were divided into three groups. Treatment group T1 was kept as a control group with no linseed supplementation, whereas treatment group T2 received ground linseed at the rate 10% of concentrate per day per animal, and treatment group T3 received 20% ground linseed. The concentration of triglycerides, cholesterol and LDL concentration were found to be significantly lower (P < 0.05) in both 10% and 20% linseed supplemented group than the control group. Whereas, HDL concentration in T2 and T3 group were found to be significantly higher than the control group. The differential expression of targeted genes comparatively revealed highest relative expression in the group that received 20% linseed supplementation. Although the study did not show a significant effect of linseed supplementation on the expression of TLR-2 and IL-2 genes in goats, it highlights the potential benefits of omega-3 PUFA supplementation on immune system modulation in animals.

Suitability of Improved and Ancient Italian Wheat for Bread-Making: A Holistic Approach

Ancient and old wheat grains are gaining interest as a genetic reservoir to develop improved Italian genotypes with peculiar features. In this light, the aim of this study was to assess the baking performance of two improved einkorn (Monlis and Norberto) and two improved emmer (Padre Pio and Giovanni Paolo) genotypes in comparison with two Italian landraces (Garfagnana and Cappelli) and Khorasan. This set was evaluated following a holistic approach considering the flour, dough, and bread properties. The results showed that the flour properties, dough rheology, pasting, and fermentation parameters, as well as the bread properties, significantly differed among the studied genotypes. Cappelli produced the bread with the best quality, i.e., the highest volume and lowest firmness. Despite having the same pedigrees, Giovanni Paolo and Padre Pio resulted in significantly different technological properties. Giovanni Paolo flour showed the highest protein content and provided a dough with a high gas production capacity, resulting in the bread having a similar firmness to Cappelli. Padre Pio flour provided bread having a similar volume to Cappelli but a high firmness similar to Khorasan and Garfagnana. The einkorn genotypes, Monlis and Norberto, showed poor fermentation properties and high gelatinization viscosity that resulted in bread with poor quality. Alternatively, they could be more suitable for making non-fermented flatbreads. Our results showed that the improved wheat showed a high versatility of features, which offers bakers a flexible material to make a genotype of bread types.

Antioxidant Status, Blood Constituents and Immune Response of Broiler Chickens Fed Two Types of Diets with or without Different Concentrations of Active Yeast

Simple Summary

Rations for broilers can be safely supplemented with probiotics such as active Saccharomyces cerevisiae (SC) yeast to stimulate oxidative reactions and immune response against stress and infectious agents. The current study suggested that SC yeast enhanced antioxidant capacity, growth rate, immune organ weights, immune response and the survival rate of broilers after Avian Influenza virus challenge at 38 days of age.

Abstract

Probiotics, such as active yeasts, are widely used to enhance poultry production and reduce feeding costs. This study aimed to investigate the antioxidant and immune responses of broilers to different concentrations of active Saccharomyces cerevisiae (SC) when supplemented to two types of diets. A total of 216 1-day-old Arbor Acres unsexed chicks were used in a factorial design, involving two feeds (regular- versus low-density diet) and three concentrations of SC (0%, 0.02% and 0.04%). The results revealed that the low-density diet reduced the body weight and production index of broilers. The addition of SC improved the production index more than the control diet. Total antioxidant capacity (TAC), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and eosinophils were significantly higher in response to the regular-density diet than the low-density diet; however, phagocytic activity (PA), lymphocyte and lysozyme activity (LYS) were lower. Saccharomyces cerevisiae reduced ALT, AST, malondialdehyde (MAD) and TAC more than the standard set, but improved packed cell volume (PCV), hemoglobin (Hgb), red blood cells (RBCs), lymphocytes, monocytes, heterophils, phagocytic index (PI) and the immune response to Newcastle disease virus (NDV) and avian influenza (AI). In conclusion, supplementation of a regular- or low-density diet with SC at a concentration of 0.02% or 0.04% improved the antioxidant parameters, immune status and production index of broilers against stress and infectious agents.

Effect of Oils in Feed on the Production Performance and Egg Quality of Laying Hens

With the development of a large-scale and intensive production industry, the number of laying hens in China is rapidly increasing. Oils, as an important source of essential fatty acids, can be added to the diet to effectively improve the production performance and absorption of other nutrients. The present review discusses the practical application of different types and qualities of oils in poultry diets and studies the critical effects of these oils on production performance, such as the egg weight, feed intake, feed conversion ratio (FCR), and various egg quality parameters, including the albumen height, Haugh units, yolk color, and saturated/unsaturated fatty acids. This article reviews the effects of different dietary oil sources on the production performance and egg quality of laying hens and their potential functional mechanisms and provides a reference for the selection of different sources of oils to include in the diet with the aim of improving egg production. This review thus provides a reference for the application of oils to the diets of laying hens. Future studies are needed to determine how poultry products can be produced with the appropriate proper oils in the diet and without negative effects on production performance and egg quality.

Body weight, organ development and jejunal histomorphology in broiler breeder pullets fed n-3 fatty acids enriched diets from hatch through to 22 weeks of age

Dietary long chain polyunsaturated n-3 fatty acids (n-3 FA) may be beneficial to broiler breeder (BB) development. Therefore, the effects of feeding sources of docosahexaenoic acid (DHA) and α-linolenic acid (ALA) from hatch through to 22 weeks of age (woa) on growth, organ weight, and jejunal histomorphology were investigated. A total of 588-day-old Ross × Ross 708 BB were reared on one of 3 diets: 1) control, corn-soybean meal diet, 2) Control + 1% microalgae (DMA, Aurantichytrium limacinum), as a source of DHA and 3) Control + 2.50% co-extruded full fat flaxseed and pulse mixture (FFF, 1:1 wt/wt), as a source of ALA. Diets DMA and FFF had similar total n-3 and n-6: n-3 ratio. Diets were allocated to floor pens (28 birds/pen) to give 9 or 6 replicates per diet for control or DMA and FFF, respectively and fed according to breeder curve in 3 phases: starter (0-4 woa), grower (5-19 woa), and pre-breeder (20-22 woa). Individual body weight (BW) was taken weekly and 6 birds/pen necropsied at 5 and 12 woa for gastrointestinal, spleen, bursa, and liver weight and samples for jejunal histomorphology. There was no (P > 0.05) diet effect on growth by 20 woa. With exception of 5 woa, pullets fed DMA showed (P < 0.001) lower BW coefficient of variation (C.V.) than pullets fed control between 2 and 7 woa. However, pullets fed DMA had higher BW CV at 20 woa than birds fed either control or FFF. At 5 woa, birds fed DMA had taller (P ≤ 0.01) villi and deeper crypt than birds fed either control or FFF but VH or CD were similar (P > 0.05) between CON and FFF pullets. At 12 woa, birds fed FFF had taller VH than birds fed control diet but similar (P > 0.05) to that of birds fed DMA. Therefore, different responses to sources of omega-3 FA may implicate other components, however, the BW uniformity and intestinal histomorphology responses suggested benefits of feeding omega-3 FA during rearing.

Dietary source of polyunsaturated fatty acids influences cell cytotoxicity in broiler chickens

The current study aims to investigate the effects of dietary source of n-3 polyunsaturated fatty acids (PUFA) on immune response in broiler chickens, represented by cytotoxic cell activity. A total of 255 one-day-old male Cobb 500 broiler chickens were fed on fish oil (FO)-, flaxseed oil-enriched diets at 50 and 19 g/kg, respectively, in addition to the soybean-based control diet. At slaughter, samples of blood and spleen were harvested from 20 birds/treatment (n = 20). The immune tissues' fatty acid profile was analyzed by gas chromatography, and the cytotoxic cell activity was investigated. The results showed that supplementing broiler chickens with diets rich in n-3 PUFA had a substantial effect on the broiler immune tissues' fatty acid profile. Cytotoxic cell activity was significantly higher in splenocytes and peripheral blood mononuclear cells (PBMCs) from broilers fed flaxseed oil than those provided FO and the soybean control diet. These results suggest that flaxseed oil may be used to enrich chickens with n-3 PUFA and improve the immune status of chicken flocks to resist diseases.

Potential role of important nutraceuticals in poultry performance and health - A comprehensive review

Antibiotics use in poultry as a growth promoter leads to the propagation of antibiotic-resistant microorganisms and incorporation of drug residues in foods; therefore, it has been restricted in different countries. There is a global trend to limit the use of antibiotics in the animal products. Prevention of the antibiotics use in the poultry diets led to the reduction in the growth performance. Consequently, there is a high demand for natural substances that lead to the same growth enhancement and beneficially affect poultry health. These constituents play essential roles in regulating the normal physiological functions of animals including the protection from infectious ailments. Nutraceuticals administration resulted beneficial in both infectious and noninfectious diseases. Being the natural components of diet, they are compatible with it and do not pose risks associated with antibiotics or other drugs. Nutraceuticals are categorized as commercial additives obtained from natural products as an alternative feed supplement for the improvement of animal welfare. This group includes enzymes, synbiotics, phytobiotics, organic acids and polyunsaturated fatty acids. In the present review, the summary of various bioactive ingredients that act as nutraceuticals and their mode of action in growth promotion and elevation of the immune system has been presented.

Effects of Taraxacum and Astragalus extracts combined with probiotic Bacillus subtilis and Lactobacillus on Escherichia coli-infected broiler chickens

Diarrhea caused by Escherichia coli (E. coli) is one of the most common diseases that affects the growth and development of poultry. This study was conducted to investigate the synergistic effects of traditional Chinese medicine (TCM) combined with probiotics against E. coli infection and its mechanism in broiler chickens. The optimal proportion formula TCM and probiotics was screened by orthogonal test and range analysis method; the in vitro antibacterial activity was based on the Oxford cup method. Isolated pathogenic E. coli was injected subcutaneously into the neck of the broilers to establish an E. coli-infected model. The broilers were administrated with drugs in drinking water daily for 7 d before and after E. coli infection. The diarrhea rate, mortality, body weight (BW) gain, feed intake, immune organ index, intestinal and hepatic histopathological changes were monitored. The expression of IL-2, IL-10, and TLR-4 mRNA in the intestinal tissues was measured by RT-PCR. Our results showed that the optimal proportion formula of Taraxacum extracts: total flavonoids of Astragalus: polysaccharides of Astragalus: probiotics was 5: 2: 2: 2; TCM combined with probiotics was highly sensitive to E. coli. TCM combined with probiotics synergistically increased BW gain, decreased the diarrhea rate and mortality of broilers, alleviated intestinal and hepatic pathological changes, accompanied by the increase of IL-2 and IL-10 mRNA expression and the inhibition of TLR-4 mRNA expression. It suggests that the combination of TCM and probiotics may produce a synergistic protective effect against E. coli infection by improving the indicators of diarrhea and regulating the expression of IL-2, IL-10, and TLR-4 mRNA in broiler chickens. The synergistic interactions between TCM and probiotics represent a promising strategy for the treatment of E. coli infection.

Supplementation of vitamin E and omega-3 fatty acids during the early posthatch period on intestinal morphology and gene expression differentiation in broilers

Early posthatch nutrition is important for gut health. Vitamin E (VE) and omega-3 (n-3) fatty acids can improve gut health through antioxidative and anti-inflammatory effects. The objective of this study was to identify the effects of VE, n-3 fatty acids, and combination of both during the starter phase (0–10 d) or grower phase (11–24 d) on intestinal morphology and expression of genes associated with gut health. A total of 210 Ross 708 broilers were randomly assigned into 7 treatments with 10 replicates of 3 birds each. The control group was fed a corn–soybean meal–basal diet during the entire study (0–58 d). Supplementation of VE (200 IU/kg), n-3 fatty acids (n-6/n-3 ratio of 3.2:1), and combination of both were fed during the starter phase (0–10 d) or grower phase (11–24 d). All of the broilers were harvested at 58 d of age. Villus height, crypt depth, villus width, distance between villi, and number of intraepithelial lymphocytes were obtained. Expression of 21 genes was measured using NanoString analysis. Expression of solute carrier family 15 member 1 (P = 0.01) associated with peptide transport and mucin 2 (P = 0.03) related with intestinal mucus barrier was increased in the broilers supplemented with n-3 fatty acids in the grower diet compared with the control. Expression of solute carrier family 7 member 1 associated with amino acid transport was decreased in the group supplemented with n-3 fatty acids during the starter phase compared with the group supplemented with n-3 fatty acids (P = 0.01) or VE and n-3 fatty acids during the grower phase (P = 0.03). These data suggest that VE and n-3 fatty acids supplemented during the grower phase have a positive effect on improving nutrient transport with n-3 fatty acids supplementation in the grower diet showing the most beneficial effect. These findings can be used in the development of nutritional management strategies to improve broiler growth performance and meat quality.

Lipid Source and Peroxidation Status Alter Immune Cell Recruitment in Broiler Chicken Ileum

BACKGROUND

Restaurant oil in poultry diets increases energy content, reduces production costs, and promotes sustainability within the food supply chain. However, variable oil composition and heating temperatures among restaurant oil sources can impact broiler chicken health due to heat-induced lipid modifications.

OBJECTIVES

A 21-d experiment was conducted to evaluate ileal morphology, liver cytokine gene expression, and ileal immune cell populations in broilers fed control or peroxidized lipids with varying chain and saturation characteristics.

METHODS

Day-old broilers were housed in battery cages (5 birds per cage) and fed diets containing 5% control or peroxidized oils. Eight diets were randomly assigned in a 4 × 2 factorial arrangement consisting of oil source (palm, soybean, flaxseed, or fish) and peroxidation status (control or peroxidized). At day 21, samples were collected for ileal histomorphology [villus height (VH), crypt depth (CrD), and the VH:CrD ratio], and liver cytokine expression (qPCR). Ileum cytokine expression and T-cell markers were analyzed by RNAscope in situ hybridization (ISH). Data were analyzed as a mixed model (SAS 9.4) with fixed effects of lipid source, peroxidation, and lipid × peroxidation interaction.

RESULTS

CD3+ T-cells in the ileum decreased 16.2% due to peroxidation (P = 0.001) with 30.3% reductions observed in birds fed peroxidized flaxseed oil (P = 0.01). Peroxidation increased IL6+ and IL1B+ cells by 62.0% and 40.3%, respectively (P = 0.01). Soybean oil increased IFNG+ cells by 55.1% compared with palm oil, regardless of peroxidation status (P = 0.007). Lipid source and peroxidation did not alter ileal histomorphology or liver cytokine expression.

CONCLUSIONS

Lipid peroxidation increased ileal IL1B and IL6 in broiler chickens, whereas soybean oil diets increased IFNG. Generally, peroxidation decreased overall CD3+ T-cell populations, suggesting impaired T-cell presence or recruitment. These results identify potential immunomodulatory lipid profiles in restaurant oil while supporting RNAscope-ISH as a method to describe avian tissue-level immune responses.

Evaluation of various levels of sweet almond meal as a source of protein on the production variables and immune response of broiler chickens

This study was conducted to evaluate effects of a sweet almond meal (SAM) as a source of protein on performance and immune responses of broiler chickens. Treatments consisted of different levels of SAM (7%, 14%, 21% and 28% of diet) and control diet that was performed in a completely randomized design in 42 days. Body weight gain (BWG) and feed intake (FI) were recorded weekly. Carcass characteristics and blood variables were measured on the 42 day of age. Immune response to sheep red blood cell (SRBC) was assessed at d 35 and d 42 (7 days after each injection). White blood cell count was done at d 28. The results showed that chickens fed 28% of SAM had lowest FI during the experiment. During grower period and also whole period of experiment, BWG was highest in chickens that consumed 7% SAM. Feed conversion ratio (FCR) significantly increased in chickens fed 28% SAM compared to the other treatments during grower period and also whole period of the experiment. The relative weight of thigh and breast significantly decreased and the relative weight of GIT increased by increasing levels of SAM in the diet. The concentration of cholesterol and LDL significantly decreased in chickens that consumed SAM in the diet. However, the highest glucose and HDL concentration were observed in chickens fed 28% SAM in the diet. Treatments did not have a significant effect on the immune response of broilers (primary and secondary SRBC antibody titres, relative weights of spleen and bursa of fabricius and white blood cell count) (p > 0.05). The results of this study show that a diet supplemented with SAM at the level of 14%, due to the improved FCR and decreased blood cholesterol and LDL concentration, can be a good replacement for soybean meal in broiler chicken's nutrition.

Effect of dietary n-3 polyunsaturated fatty acids on the composition of cecal microbiome of Lohmann hens

Supplementation of n-3 fatty acids to poultry diets is widely acknowledged for its role in enhancing poultry products, however, little is known about the compositional responses of gut microbial communities to type and dosage of these supplements.  Here, we compared the effects of n-3 polyunsaturated fatty acids (PUFA), supplied as alpha-linolenic acid (ALA) or docosahexaenoic acid (DHA), on the composition of bacterial communities in ceca of laying hens.  Corn-soybean basal diets were supplemented with either flaxseed oil (FO, ALA-rich) or marine algal biomass (MA, DHA-rich), and each supplied 0.20 and 0.60% of total n-3 PUFA in the diet.  Lohmann LSL-Classic laying hens (n = 10/treatment) were randomly allocated to one of the 4 diets.  After 8 weeks of feeding, blood, liver and cecal digesta samples were obtained for plasma glucose, fatty acids, and short chain fatty acids analyses, respectively.  The gut bacterial communities were characterized using genomic DNA extracted from cecal contents, whereby the V3-V4 hypervariable region of the 16S rRNA gene was sequenced using the Illumina Miseq® platform.  Firmicutes and Bacteroidetes were the predominant phyla in both the FO- and MA-fed groups.  The relative abundance of Tenericutes, often associated with immunomodulation, was relatively higher (P<0.0001) in the FO than MA group.  Although the relative abundance of Bacteroides was greater for the FO- than the MA-fed group, this genus was negatively correlated (P<0.05) with total n-3 PUFA in the liver at higher dosages of both FO- and MA-fed hens.  Higher dose of FO (0.60%) and both dosages of MA (0.20 and 0.60%) substantially enriched several members of Firmicutes (e.g., Faecalibacterium, Clostridium and Ruminococcus) which are known to produce butyrate.  Moreover, co-occurrence network analysis revealed that, in the FO 0.60- and MA 0.20-fed hens, Ruminococcaceae was the most influential taxon accounting for about 31% of the network complexity.  These findings demonstrate that supplementation of different type and level of n-3 PUFA in hens' diets could enrich microbial communities with potential role in lipid metabolism and health.

Modulatory Effect of Dietary Polyunsaturated Fatty Acids on Immunity, Represented by Phagocytic Activity

Lately, dietary polyunsaturated fatty acids (PUFAs) have shown substantial importance in human and animal nutrition, especially those of the n-3 group. Development and optimal functioning of the immune system are directed affected by diet. These dietary fatty acids have an important impact on the health and immune competence of various species including human beings. They are essential for the modulation of immune responses in health and disease. Fatty acid composition of immune cells can be modulated by the action of dietary fats and the outcomes in the composition can produce functional effects on reactivity and functioning of immune cells in a short period. There are several mechanisms involved in impacting dietary fatty acids on immune function; however, lipid mediator synthesis from PUFAs is of great importance in terms of inflammation. The objectives of this article are reviewing studies on the impact of PUFA in the diet on phagocytosis of chickens, murine, rats, ruminants, and humans. It also sheds light on the possible mechanism by which this immunomodulation occurs.

Comparison of toxic effects of dietary organic or inorganic selenium and prediction of selenium intake and tissue selenium concentrations in broiler chickens using feather selenium concentrations

The present experiment aimed to compare toxic effects of dietary organic or inorganic selenium (Se) and to predict of Se intake and tissue Se concentrations in broiler chickens based on feather Se concentrations. A total of four hundred twenty 7-day-old Ross 308 male broiler chicks were allotted to 1 of 7 dietary treatments in a completely randomized design. Each treatment had 6 replicates with 10 birds per replicate. Organic Se (selenium yeast) or inorganic Se (sodium selenite) was added to the basal diet at the levels of 5, 10, or 15 mg/kg Se. All experimental diets were fed to birds on an ad libitum basis for 28 d. Results indicated that a significant interaction (P < 0.01) was observed between Se sources and inclusion levels for the BW gain and feed intake of broiler chickens with inorganic Se at 15 mg/kg in diets showing a greatest negative effect. Increasing inclusion levels of Se in diets increased (linear, P < 0.01) plasma concentrations of uric acid. Increasing inclusion levels of Se in diets increased (linear, P < 0.01) relative liver weight. No significant interactions were observed between Se sources and inclusion levels in diets on hepatic antioxidant capacity. Increasing inclusion levels of Se in diets increased (linear, P < 0.01) Se concentrations in the liver, breast, and feather. The concentrations of Se in the breast, liver, and feather were greater (P < 0.05) for organic Se than for inorganic Se in diets. The toxic levels of organic or inorganic Se in broiler diets were near 7 or 9 mg/kg based on the BW gain, respectively. The prediction equations indicate that feather Se concentrations in broiler chickens can be used to predict both daily Se intake and Se concentrations in the liver and breast.

Challenges to the Poultry Industry: Current Perspectives and Strategic Future After the COVID-19 Outbreak

Poultry immunity, health, and production are several factors that challenge the future growth of the poultry industry. Consumer confidence, product quality and safety, types of products, and the emergence and re-emergence of diseases will continue to be major challenges to the current situation and the strategic future of the industry. Foodborne and zoonotic diseases are strictly linked with poultry. Eradication, elimination, and/or control of foodborne and zoonotic pathogens present a major challenge to the poultry industry. In addition, the public health hazards from consuming foods with high antibiotic residues will remain a critical issue. The theory of poultry production described in this review will not be limited to considering disease control. Rather, it will also incorporate the interconnection of the animals' health, welfare, and immunity. It is essential to know that chickens are not susceptible to intranasal infection by the SARS-CoV-2 (COVID-19) virus. Nevertheless, the COVID-19 pandemic will affect poultry consumption, transport, and the economics of poultry farming. It will also take into consideration economic, ethical, social dimensions, and the sustenance of the accomplishment of high environmental security. Stockholders, veterinarians, farmers, and all the partners of the chain of poultry production need to be more involved in the current situation and the strategic future of the industry to fulfill human demands and ensure sustainable agriculture. Thus, the present review explores these important tasks.

Dietary Supplementation With Various Fat Oils Affect Phytohemagglutinin Skin Test in Broiler Chickens

The current study aimed to investigate the effect of different dietary supplemental oils on the immune status of broilers. One-day-old Cobb 500 broiler chicks were randomly distributed into eight batteries and fed eight experimental diets. There were 680 broilers, 85 birds per battery. The experimental oils were all used at 10% of the total diet. Each dietary treatment (TRT) contained one of the following essential oils: TRT 1 = control group that received a basal diet + soybean oil (SO); TRT 2 = basal diet as in TRT 1 + sunflower oil (SFO); TRT 3 = basal diet as in TRT 1 + canola oil (CO); TRT 4 = basal diet as in TRT 1 + flaxseed oil (FLO); TRT 5 = basal diet as in TRT 1 + fish oil (FO); TRT 6 = basal diet as in TRT 1 + mix of fish oil and soya oil (SO + FO); TRT 7 = basal diet as in TRT 1 + algal biomass oil (DHA); TRT 8 = basal diet as in TRT 1 + echium oil (EO). All samples were taken from 10 birds per treatment (n = 10). The immune parameters investigated involved measurement of weights of immune organs as a general indicator, hemocytometric measurements, intestinal microbial count and hindgut acidosis, hindgut volatile fatty acids, and cellular immune response using phytohemagglutinin test. The use of the different dietary treatments did not affect the general health status of the chickens, and the mortality was minimal with no signs of illness or outbreaks. The fact that both the control and the treatment diets were equally consumed would indicate that supplemental oil inclusions did not adversely affect the palatability of the diet by the chickens. At 3 weeks of age, there was no significant effect observed in the microbial counts of the intestine. However, at 5 weeks of age, the highest microbial count was significantly observed for broilers fed EO (7.30%), closely followed by SFO (6.95%), and the least microbial counts were observed for CO (5.63%). No significance was observed for lactic acid bacteria (LAB) and Salmonella. There was no significance observed for the effect of the dietary treatments on the hindgut volatile acid in the broilers. Wattle swelling changes were significant between dietary treatments. The results revealed that dietary FLO, FO, and DHA oils induced higher cellular response than the other treatments (P = 0.035), representing higher cellular response in these groups. In conclusion, supplemental oils rich in n−3 fatty acids may enhance the immune response in broiler chickens, represented by the intestinal microbial counts and the cellular immune response.

The Effects of Different Oil Sources on Performance, Digestive Enzymes, Carcass Traits, Biochemical, Immunological, Antioxidant, and Morphometric Responses of Broiler Chicks

This research evaluate the influence of different oil sources, namely fish oil (FO), coconut oil (CocO), canola oil (CanO), or a mixture of the three oils (MTO)—included at 1.5% in broiler diets—compared to a no oil-supplemented diet. Hence, 250 unsexed, 1-day-old Cobb chicks were weighed and randomly allocated into five dietary treatment groups of 50 chicks each and five replicates per group. Oil-supplemented diets significantly increased the growth, improved the feed conversion ratio (FCR), and decreased the abdominal fat percentage compared to the control diet. Amylase was significantly elevated due to feeding the FO- or CocO-supplemented-diet compared to the control diet, whereas lipase increased due to offering CocO- and CanO-enriched diet; chymotrypsin increased due to different oil sources. High-density lipoprotein cholesterol (HDL-C) increased markedly due to offering an oil-supplemented diet, but low-density lipoprotein cholesterol (LDL-C), the LDL-C:HDL-C ratio, and malondialdehyde (MDA) decreased. Blood plasma immunoglobulin (Ig) G and IgM significantly increased due to feeding CocO, CanO, or MTO compared to the control group, whereas FO increased IgG only. FO- and CanO-containing diets resulted in the highest increase in α2-globulin and γ-globulin. The antibody titer to avian influenza (HIAI) and Newcastle disease (HIND) were significantly elevated due to CocO supplementation compared to the control group. The bursa follicle length and width and thymus cortex depth were increased considerably due to the FO-supplemented diet compared to the control, but the follicle length:width ratio decreased. The villus height:depth ratio was significantly elevated due to both the CanO and MTO diets. The antioxidant status improved considerably due to the addition of CocO and CanO. Both CanO and MTO similarly increased plasma T3, T4, and the T3:T4 ratio. In conclusion, oil supplementations at 1.5% enhanced growth performance and immune status, improved the blood lipid profile and antioxidants status, and the effect of the oil sources depends on the criteria of response.

Impact of Multienzymes Dose Supplemented Continuously Or Intermittently in Drinking Water on Growth Performance, Nutrient Digestibility, and Blood Constituents of Broiler Chickens

The aim of this work was to study the continuous or intermittent impact of a multienzyme supplement on growth performance, nutrient digestibility, and blood metabolites of broilers, and to evaluate production index of dietary supplementation. A total of 315 unsexed day-old Arbor Acres broiler chicks were randomly distributed to seven treatments groups, keeping initial body weights similar, in 35-floor pens (replicates) of nine chicks per replicate (pen) and five experimental units per treatment. All experimental groups were fed the same basal diet and administered seven multienzyme treatments: the 1st group (control) did not receive any enzyme supplementation; the 2nd, 3rd, and 4th groups were administered multienzymes at 0.5, 1.0, and 1.5 mL/L drinking water, respectively. Each enzyme supplemented-group was divided into two subgroups, with additives being applied either continuously (24 h/day) or intermittently (12 h/day) from 1 to 35 days old. Regardless of administration method, multienzyme supplements at 1.0 mL/L water along with a corn-soybean meal diet increased the body weight gain (BWG) by 7.8% compared to 0.5 mL/L water during days 1-21 of age. In addition, 1.5 mL/L water significantly improved BWG by 5.1% of broilers compared to 0.5 mL/L water during days 1-35 of age. Enzyme supplementation at 1.5 mL/L water significantly enhanced feed conversion ratio (FCR) by 4.3% during days 1-21 of age, and FCR by 5.2% and European production index (EPI) by 10.4% during days 1-35 of age compared to the group on 0.5 mL/L water. For the whole period, there were improvements of beneficial consideration in BWG (4.0%), FCR (4.0%), and European production index (8.2%) due to continuous multienzyme supplementation at 0.5 mL/L water compared to the same dose added intermittently. A similar trend was observed due to intermittent multienzymes at 1 mL/L drinking water that resulted in increased BWG by (6.4%) and improved FCR by (6.7%) and EPI by (12.7%). Intermittent administration significantly increased feed intake of broilers during 22-35 days of age compared to continuous supplementation. Multienzymes at different doses did not significantly affect the digestibility of nutrients, blood serum biochemical constituent, inner body organs, and markers of functions of liver and renal organs. In conclusion, the highest BWG and the best FCR and EPI for the whole period were from broilers given continuous 1 and 1.5 mL/L drinking water or intermittent multienzyme supplementation at 1.5 mL/L drinking water. Furthermore, intermittent supplementation of enzymes at 1 mL/L drinking water and continuous supplementation at 0.5 mL/L drinking water can be investigated in further experiments as a tool to improve broiler growth performance and economic traits and to decrease the cost of enzyme application.

Comparison of different dietary sources of n-3 polyunsaturated fatty acids on immune response in broiler chickens

The study aims to research the effects of varied dietary sources of n-3 polyunsaturated fatty acids (PUFA) on the immune response in broiler chickens with stress on natural killer (NK) cell activity. Diets supplemented with one of the four sources of n-3 PUFA: linseed oil-, echium oil-, fish oil (FO) or algal biomass-enriched diets at levels of 18, 18, 50 and 15 g/kg fresh weight, were provided for one-d-old male Ross 308 broilers, totaling 340 in number, until they were slaughtered. The analyses included total lipid profile using gas chromatography (GC) for plasma, spleen, thymus, and blood. Additionally, NK cell activity and cell proliferation were investigated for thymocytes and splenocytes. The results indicated that the source of n-3 PUFA had a strong influence on fatty acid composition across all tissues. NK activity was highest in splenocytes and PBMCs from broilers fed linseed oil, followed by those fed algal biomass or echium oil, and lowest for those from broilers fed FO. The proliferative response of lymphocytes from algal biomass-fed chickens tended to be the highest, followed by those fed linseed oil in most cases. Lymphocytes from chickens fed fish oil showed the lowest proliferative response. These results could mean that a docosahexaenoic acid (DHA)-rich algal product might enrich chicken meat with n-3 PUFA without significant damaging effects on chicken immunity.

Effect of vitamin E sources and inclusion levels in diets on growth performance, meat quality, alpha-tocopherol retention, and intestinal inflammatory cytokine expression in broiler chickens

Water-miscible vitamin E (WVE) has been known to be more bioavailable than conventional lipid-soluble vitamin E (LVE) in human foods because of its greater solubility in the gastrointestinal tract. However, no data regarding the comparison of the efficacy of WVE to LVE were available in poultry diets. The objective of the current experiment was to investigate the effect of vitamin E (VE) sources and inclusion levels in diets on growth performance, meat quality, alpha-tocopherol retention, and intestinal inflammatory cytokine expression in broiler chickens. A total of 420 6-d-old broiler chicks were allotted to 1 of 7 dietary treatments with 6 replicates in a completely randomized design. The corn-soybean meal-based basal diet was formulated without inclusion of supplemental VE. Additional 6 diets were prepared by supplementing the basal diet with either WVE or LVE at the inclusion levels of 33, 65, or 100 IU/kg in diets. Diets were fed to birds for 26 d. Results indicated that different VE sources and inclusion levels from 33 to 100 IU/kg in diets had no effects on growth performance in broilers. The VE sources did not affect lipid oxidation in both breast and thigh meat. However, increasing inclusion levels of VE decreased (linear and quadratic, P < 0.05) lipid oxidation in breast meat. Regardless of VE sources, increasing inclusion levels of VE increased (linear, P < 0.01) alpha-tocopherol concentrations in breast meat. Dietary WVE showed a greater reduction in the expression of both pro- and anti-inflammatory cytokine genes in the jejunum than dietary LVE. Increasing inclusion levels of both VE sources decreased (linear and quadratic, P < 0.05) the expression of both pro- and anti-inflammatory cytokine genes in the jejunum. The efficacy of dietary WVE for growth performance, meat quality, lipid oxidation, and alpha-tocopherol retention in broilers chickens is similar to that of dietary LVE. However, it is likely that dietary WVE is more effective in decreasing intestinal inflammatory responses than dietary LVE in broilers.

Omega-3 and Omega-6 Fatty Acids in Poultry Nutrition: Effect on Production Performance and Health

Omega-3 (ω-3) and omega-6 (ω-6) fatty acids are important components of cell membranes. They are essential for health and normal physiological functioning of humans. Not all fatty acids can be produced endogenously owing to the absence of certain desaturases; however, they are required in a ratio that is not naturally achieved by the standard diet of industrialized nations. Poultry products have become the primary source of long-chain polyunsaturated fatty acids (LC-PUFA), with one of the most effective solutions being to increase the accretion of PUFAs in chicken products via the adjustment of fatty acids in poultry diets. Several studies have reported the favorable effects of ω-3 PUFA on bone strength, bone mineral content and density, and semen quality. However, other studies concluded negative effects of LC-PUFA on meat quality and palatability, and acceptability by consumers. The present review discussed the practical application of ω-3 and ω-6 fatty acids in poultry diets, and studied the critical effects of these fatty acids on productive performance, blood biochemistry, immunity, carcass traits, bone traits, egg and meat quality, and semen quality in poultry. Future studies are required to determine how poultry products can be produced with higher contents of PUFAs and favorable fatty acid composition, at low cost and without negative effects on palatability and quality.

Fatty Acid Content and Tumor Growth Changes in Mice After Exposure to Extremely High-Frequency Electromagnetic Radiation and Consumption of N-3 Fatty Acids

The topical problem is to find new, more effective and safe treatments for cancer. The purpose of the present work was to study the combined effects of low-intensity extremely high-frequency electromagnetic radiation (EHF EMR) and consumption of n-3 polyunsaturated fatty acids (PUFAs) on tumor growth and the content of FAs in the thymus and tumor tissue in mice. Fatty acid composition was determined using gas chromatography. Exposure of tumor-bearing mice with solid Ehrlich carcinoma to EHF EMR with effective parameters (42.2 GHz, 0.1 mW/cm², 20 min daily for 5 consecutive days beginning on the first day after the tumor inoculation) led to delaying the tumor growth and restored the content of almost all FAs in thymic tissue to the level of intact animals. Animal intake of the preparation enriched with n-3 PUFAs increased the content of n-3 PUFAs in thymic tissue significantly, but did not affect the tumor growth, even in combination with EHF EMR exposure. Combined action of EHF EMR exposure and n-3 preparation promoted recovery of thymus weight in tumor-bearing animals. The data obtained assume a complex interaction between the immune system and the tumor, and the important role of FAs in the regulation of this interaction.

On growth performance, nutrient digestibility, blood T lymphocyte subsets, and cardiac antioxidant status of broilers

Different lipid sources differ in the fatty acid profiles and differently affect growth performance as well as immune function of broilers. The influences of different dietary lipid sources on growth performance, nutrient digestibility, blood T lymphocyte population, and cardiac antioxidant status were investigated of broilers. A total of 360 one-day-old male broilers (BW = 44 ± 3 g) were randomized into 3 treatment groups, consisting of 6 replicates with 20 birds in each group. Broilers received standard diets supplemented with 5% (wt/wt) of lard (LD, as a control diet), sesame oil (SO), or flaxseed oil (FO). Broilers in both SO and FO treatment groups had lower (P < 0.05) feed conversion ratios from 22 to 42 d and during the overall phase compared to those in LD treatment group. Meanwhile, the apparent total tract nutrient digestibility of crude fat in SO and FO treatment groups was higher than that in LD treatment group. Both FO and SO treatments decreased (P < 0.05) abdominal fat percentage compared to LD treatment. Total triglycerides and total cholesterol in chicken blood were decreased (P < 0.05) by SO and FO treatments compared to LD treatment. Feeding broilers with FO and SO led to a decrease (P < 0.05) in blood CD4⁺ T lymphocyte count and in CD4⁺:CD8⁺ ratio compared to LD treatment. Sesame oil and FO treatments increased cardiac glutathione peroxidase (P < 0.05) compared to LD treatment. It is concluded that addition of 5% SO and FO to the standard corn-soybean meal diet improved feed efficiency, increased the activities of cardiac glutathione peroxidase, and affected the T lymphocytes ratio of fast growing broilers.

Interactive effects of dietary lipids and vitamin E level on performance, blood eicosanoids, and response to mitogen stimulation in broiler chickens of different ages

The effects of the dietary polyunsaturated fatty acids (PUFA) n-6:n-3 ratio and vitamin E (vE) on the levels of pro-inflammatory eicosanoids, the incorporation of docosahexaenoic acid (DHA) and arachidonic acid (AA) into immune tissues, and changes in leukocyte population after phytohemagglutinin (PHA) challenge were investigated in broiler chickens of different ages. One-day-old female broilers (48 per treatment) were fed 4 different wheat-soybean-corn-based diets containing corn oil with a high PUFA n-6:n-3 ratio (HR) or a mixture of linseed and fish oils with a low PUFA n-6:n-3 ratio (LR). Diets contained either 50 mg vE kg-1 of diet (basal vE) or 300 mg vE kg-1 of diet (increased vE). At d 14 and d 34, 8 chickens per treatment were challenged with PHA, and wing web swelling (WWS) was measured. The blood concentration of leukotriene (LTB4), prostaglandin (PGE2), and thromboxane (TBX2) in 17-day-old and 43-day-old chickens was determined. The pattern of AA and DHA incorporation into bursa, spleen, and brain lipids reflected the level of their precursors in the diet. WWS was the highest in chickens fed a LR diet and in 14-day-old chickens (P < 0.01). Leukocyte proportions varied with dietary PUFA n-6:n-3 ratio and with age. The heterophil:lymphocyte ratio was the highest at 6 h post PHA challenge, and was higher in 34-day-old chickens (P < 0.001). TBX2 and PGE2 concentrations were higher in chickens fed HR diet, whereas TBX2 and LTB4 concentrations were lower at high vE level. Lower PGE2 and LTB4, but higher TBX2 concentrations were measured in younger birds (P < 0.001). The results indicated that LR increased the phagocytic cell proportion in the blood; HR promoted the incorporation of AA into the immune tissues, which increased the levels of more pro-inflammatory eicosanoids in the blood; and vE counteracts these effects to some extent. Owing to the immaturity of the immune system, dietary interventions might be promising at the early stage of chicken growth.

Managing gut health without reliance on antimicrobials in poultry

It is well established that antimicrobials in animal feed enhance feed efficiency, promote animal growth and improve the quality of animal products. However, resistance development in bacterial populations, and hence consumer demand for products free of antimicrobial residues, has prompted efforts to develop alternatives that can replace antimicrobials without causing loss of productivity or product quality. One of the key barriers to complete withdrawal from antimicrobial use is microbial infection, for example, necrotic enteritis. There is much interest in using in-feed nutraceuticals such as prebiotics, probiotics, organic acids and plant extracts as alternatives to antimicrobials to create a healthy gastrointestinal environment and to prevent and treat enteric infections. Enzymes are generally used to alleviate anti-nutritional factors in feed, but there is growing awareness of their beneficial effects on the gastrointestinal environment, and consequently on gut health. An example of this is production of prebiotic xylo-oligosaccharides when xylanase is added to feed. This review discusses developments in alternatives to antimicrobials that can aid in managing gut health in a post-antimicrobial era, with particular reference to recent nutritional strategies.

The effect of feed supplementation with zinc chelate and zinc sulphate on selected humoral and cell-mediated immune parameters and cytokine concentration in broiler chickens

The ability of poultry to withstand infectious disease caused by bacteria, viruses or protozoa depends upon the integrity of the immune system. Zinc is important for proper functioning of heterophils, mononuclear phagocytes and T lymphocytes. Numerous data indicate that the demand for zinc in poultry is not met in Poland due to its low content in feeds of vegetable origin. The aim of the study was to determine the effect of supplementation of inorganic (ZnSO₄ and ZnSO₄⁺ phytase enzyme), and organic forms of zinc (Zn with glycine and Zn with glycine and phytase enzyme) on selected parameters of the cellular and humoral immune response in broiler chickens by evaluating the percentage of CD3⁺CD4⁺, CD3⁺CD8⁺, CD25⁺, MHC Class II, and BU-1⁺ lymphocytes, the phagocytic activity of monocytes and heterophils, and the concentration of IL-2, IL-10 and TNF-α in the peripheral blood. Flow cytometry was used to determine selected cell-mediated immune response parameters. Phagocytic activity in whole blood was performed using the commercial Phagotest kit (ORPEGEN-Pharma, Immuniq, Poland). The results showed that supplementation with zinc chelates causes activation of the cellular and humoral immune response in poultry, helping to maintain the balance between the Th1 and Th2 response and enhancing resistance to infections. In contrast with chelates, the use of zinc in the form of sulphates has no immunomodulatory effect and may contribute to the development of local inflammatory processes in the digestive tract, increasing susceptibility to infection.

Can breeder reproductive status, performance and egg quality be enhanced by supplementation and transition of n-3 fatty acids?

The aim of this experiment was to investigate the effect of n-3 fatty acid (FA) supplemented diets on breeder performance, productivity and egg quality. Breeders (n = 480) were fed the supplemented diet from 18 weeks onwards; the inclusion level of n-3 FA was increased from 1.5% to 3.0% from 34 weeks of age onwards until 48 weeks of age. Ross-308 broiler breeders (n = 480) were fed one of four different diets: a basal diet rich in n-6 FA (control diet) or one of three diets rich in n-3 FA. For the n-3 FA diets, eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) were fed to the broiler breeders at different ratios formulated to obtain EPA/DHA ratios of 1/1, 1/2 or 2/1. Differences in performance, reproduction and egg quality parameters due to n-3 supplementation were noted more for the 1.5% followed by the 3.0% fed broilers than their 1.5% supplemented counterparts. Egg weight (p < 0.001) and egg mass (p = 0.003) were significantly lower and feed conversion (p = 0.008) significantly higher for the n-3 FA (at 3.0% inclusion level) fed broilers compared to the control group. For the EPA- and DHA-fed breeders, a higher proportional abdominal fat percentage (p = 0.025) and proportional albumen weight (%) (p = 0.041) were found respectively. Dietary treatments did not affect reproduction. It can be concluded that the results of the present experiment indicate no significant differences between treatments at 1.5% inclusion levels. However, increasing this level to 3.0% is not recommended due to the rather negative effects on the measured parameters. It should be further investigated whether these adverse effects were obtained due to (i) the higher supplementation level, (ii) combining a supplementation level of 1.5% with 3% or (iii) the duration of supplementation.

Effects of dietary n-6/n-3 polyunsaturated fatty acid ratios on the mass, and histological and ultrastructures of liver, spleen and thymus of 70-day-old Yangzhou goslings

The objective of this study was to determine the effects of dietary n-6/n-3 polyunsaturated fatty acid (PUFA) ratios on the organ indexes, and histological and ultrastructures of organs including liver, spleen and thymus in 70-day-old Yangzhou goslings. One-hundred and sixty 21-day-old Yangzhou goslings were randomly divided into 4 groups and fed 4 diets varying in the n-6/n-3 PUFA ratio from 3:1 up to 12:1. After 1-week acclimation, the feeding experiment lasted for 6 weeks. At the end of the experimental period, goslings were slaughtered and the liver, spleen and thymus were weighed, and their histological and ultrastructures were examined. The results showed that the organ indices in the 3:1 group were remarkably higher than in the other three groups, whereas the mitochondrial square did not differ among four groups. The histological and ultrastructures of the liver, spleen and thymus were not affected by the diets with the lower n-6/n-3 PUFA ratios (3:1 and 6:1). However, feeding diets with the higher n-6/n-3 PUFA ratios (9:1 and 12:1), the nuclear chromatin was concentrated and marginalized; the cell membrane was contracted inwardly and disrupted; the mitochondrial membrane was damaged to some degree. In conclusion, the diet containing higher content of n-3 PUFA might improve immune capacity of goslings the animal by accelerating the growth and maintaining cellular structures of organs like liver, spleen and thymus.

Effects of a dietary antioxidant blend and vitamin E on fatty acid profile, liver function, and inflammatory response in broiler chickens fed a diet high in oxidants

The aim of the current study was to determine the effects of a dietary antioxidant blend and vitamin E on fatty acid profile, inflammatory response, and liver function. Cobb 500 male broilers (n = 1,200, d 0) were randomly distributed into 6 treatments with 10 replicate floor pens. Treatments included (1) a high-oxidant diet, with vitamin E at 10 IU/kg, 3% oxidized oil, 3% polyunsaturated fatty acids (PUFA) source (HO); (2) the HO diet with vitamin E at 200 IU/kg (VE); (3) the HO diet with an antioxidant blend at 135 mg/kg (AOX); (4) the HO diet with both vitamin E at 200 IU/kg and an antioxidant blend at 135 mg/kg (VE+AOX); (5) standard control (SC); and (6) a positive control, which was the SC diet with an antioxidant blend at 135 mg/kg. The concentrations of 20:4, 20:5, 22:5, 22:6, and all the n-3 fatty acids were greater in the abdominal fat of HO, VE, AOX, and VE+AOX birds than SC and positive control birds on d 21 and 42 (P < 0.001). Compared with HO treatment, AOX and VE+AOX preserved the deposition of PUFA better (P < 0.001). The HO birds had greater concentrations of aspartate aminotransferase on d 21 and 42, and γ-glutamyl transferase on d 21, whereas AOX and VE+AOX chickens had restored γ-glutamyl transferase concentration (P < 0.01). The inflammation scores of abdominal fat of AOX and VE+AOX birds were lower than the HO on d 21 (P < 0.001). Compared with SC, the VE and VE+AOX birds exhibited greater vacuole scores on d 21 and 42 (P < 0.01). The lower vacuoles score in SC was associated with a greater expression of peroxisome proliferator activated receptor -γ and -α (P < 0.05). The expression of inflammatory genes in the liver did not differ among treatments. In conclusion, the AOX and AOX+VE diets were effective in preserving PUFA in the abdominal fat, moderately improved liver function, and reduced inflammation in fat.

Effect of dietary combination of methionine and fish oil on cellular immunity and plasma fatty acids in infectious bursal disease challenged chickens

This study was carried out to investigate the modulatory effects of dietary methionine and fish oil on immune response, plasma fatty acid profile, and blood parameters of infectious bursal disease (IBD) challenged broiler chickens. A total of 300 one-day-old male broiler chicks were assigned to one of six dietary treatment groups in a 3 × 2 factorial arrangement. There were three levels of fish oil (0, 2.5 and 5.5%), and two levels of methionine (NRC recommendation and twice NRC recommendation). The results showed that the birds fed with 5.5% fish oil had higher total protein, white blood cell count, and IL-2 concentration than those of other groups at 7 days after IBD challenge. Inclusion of fish oil in diet had no effect on IFN- γ concentration. However, supplementation of methionine twice the recommendation enhanced the serum IFN- γ and globulin concentration. Neither of fish oil nor methionine supplementation affected the liver enzymes concentration. It can be suggested that a balance of moderate level of fish oil (2.5%) and methionine level (twice NRC recommendation) might enhance immune response in IBD challenged broiler chickens.